1. Field of the Invention
The present invention relates to a silver halide photographic light-sensitive material.
2. Description of the Related Art
In the photograph industry, various studies have hitherto been made in order to increase the sensitivity and image quality of silver halide photographic light-sensitive materials. However, the industry has yet to provide materials which have photographic properties good enough to meet the recent demand for materials that can be used in various photographing conditions. To increase the sensitivity and image quality of a silver halide photographic light-sensitive material, it is necessary to enhance the sensitivity of the silver halide gains contained in the light-sensitive material. Various attempts have been made to this end.
One of these attempts is the study of chemical sensitization. Typical examples of chemical sensitization are: sulfur sensitization, selenium sensitization, precious-metal sensitization such as gold sensitization, reduction sensitization, and a combination of these sensitizations.
Tellurium sensitization is known as a chemical sensitization described above, and is generally described in, for example, U.S. Pat. Nos. 1,623,499, 3,320,069, 3,772,031, 3,531,289, and 3,655,394, British Patents 235,211, 1,121,496, 1,295,462, and 1,396,696, and Canadian Patent 800,958. However, specific tellurium sensitizers are described in detail in a few publications only, such as British Patents 1,295,462 and 1,396,696, and Canadian Patent 800,958.
Methods of forming and using silver halide tabular grains (hereinafter referred to as "tabular grains"), which are one type of the silver halide grains described above, are described in, for example, U.S. Pat. Nos. 4,434,226, 4,439,520, 4,414,310, 4,433,048, 4,414,306, and 4,459,353. These methods are known to achieve various advantages, such as increased sensitivity, including the color-sensitization efficiency increased by a sensitizing dye, an improved sensitivity/graininess ratio, increased sharpness owing to the optical properties specific to tabular grains, and increased covering power. As the recent sensitivity of tabular grains is not satisfactory, further improvement has been demanded.
The increasing of the sensitivity of tabular grains has often degraded their pressure property in some cases because of their shape. Thus, the technique of increasing the sensitivity of tabular grains, without degrading the pressure property thereof, has long been demanded.